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An anonymous reader writes "Researchers at the UK's University of Newcastle have created a new type of bacteria that generates glue to hold together cracks in concrete structures — that means everything from concrete sidewalks to buildings that have been damaged by earthquakes. When the cells have been germinated, they burrow deep into the concrete until they reach the bottom. At this point, the concrete repair process is activated, and the cells split into three types that produce calcium carbonate crystals, act as reinforcing fibers, and produce glue which acts as a binding agent to fill concrete gaps."

Dark Helmet and Sandurz come across an image of themselves viewing the screen. As they react, the screen mimics what they are doing] Dark Helmet: What the hell am I looking at?! When does this happen in the movie?!
Colonel Sandurz: "Now". You're looking at "now", sir. Everything that happens now [indicates himself and Helmet] is happening "now". [Indicates the screen]
Dark Helmet: What happened to "then"?

The problem, with bullet wound is... they are not always clean, you can have some clothes debris, or other dirt. Closing the wound is easy (well, relatively speaking) but cleaning it well enough is another thing.

Another problem with bullet wounds is emergency room doctors who believe the myth of "hydrostatic shock" damage and chop out a core of tissue around the bullet's path (as if it were a linear cancer), rather than treating it properly by cleaning and closing the wound (as if it were any other puncture-and-displacement trauma).

Yo, Docs! Even if the bullet somehow WAS traveling faster than the speed of sound in flesh (like about mach 4.4) shock waves aren't any big de

I dunno where you're getting this info, but no, bullets certainly do not "sterilize" anything. One of the leading causes of death historically has been infection. We're better at dealing with it today, but infections still occur on a regular basis:

The only real problem I can see is in an environment like the SoCal desert, where the soil pH is extremely high, and also very high in calcium salts. Seems to me you'd have to do a test-run to make sure you didn't get a runaway effect in such soils, for applications where cracks in the concrete extend all the way through. Either that, or maybe precede the treatment with an acid wash. I'm sure some such control mechanism can be developed.

(When we tested the soil on my place, the pH was so high that the teste

The Romans started using concrete before 200 B.C. [ucsb.edu], but Wikipedia says the Egyptian pyramids [wikimedia.org] were built with concrete long before that. So that makes its invention 2200-4600 years ago.

IMO "several hundred" was correct.

From your link: "being more than two but fewer than many". Considering civilization has only been around for ~60 centuries, "several" is arguably less than twenty. Try "many hundreds" next time you go for your pedantic medal. Thanks for playing.

React to the specific PH of the concrete? If only all concrete were the same. Its been in use for several hundred years, and the formula has been constantly evolving.

Remember Monsanto and "roundup ready" seeds? Now imagine a "bio-healing ready" concrete... concrete that is differentiated by a specific compound formula which is standardized for a specific bacteria (of course several grades of the product combo will exist for both quality and usage differences... which also allow for market segmentation)

All it will take is some enterprising megacorp with the legal muscle to patent this combo (and defend the patents) and you can effectively raised margin on concrete 10x at least.

Anything can be de-commoditized if it provides unique value and a big enough megacorp.

Spider silk is a remarkably strong material. Its tensile strength is comparable to that of high-grade steel (1500 MPa),[7][8] and about half as strong as aramid filaments, such as Twaron or Kevlar (3000 MPa).[9] Spider silk is about a fifth of the density of steel; a strand long enough to circle the Earth would weigh less than 500 grams (18 oz).[10] Spider silk [wikipedia.org]

and the same calcium carbonate crystals as the original concrete, so it's easily conceivable that the

Would you be happier if no one mentioned any of these "parameters"? Would that make successful development more likely? When questions are suppressed or not addressed during the early stages disasters [youtube.com] inevitably happen.

I immediately thought of Masamune Shirow's Dominion Tank Police [wikipedia.org]. Bacteria that can grow between cracks in concrete = bacteria that will grow over a lattice. Lash together a frame soaked in bacteria-food, seed the base, come back in a couple of weeks.
Now, where're my sexy android catgirls?

How is it gonna stop? when they run out of concrete to fill, when they overpopulate and eat all the concrete "cracks" or when they kill all humans and we can't record the moment it stops because there won't be any humans to observe it?

The BacillaFilla spores start germinating only when they make contact with concrete — triggered by the very specific pH of the material — and they have a built-in self-destruct gene that prevents them from proliferating away from the concrete target.

I would like to buy some--the city is doing a <sarcasm> wonderful </sarcasm> job of taking care of the sidewalk in front of my house.

The spores germinate only in very alkaline environments — concrete has a quite high pH. The article is vague on details, but notes that "[the bacteria] have a built-in self-destruct gene that prevents them from proliferating away from the concrete target."

Now, What Could Possibly Go Wrong and all of that, but the bases are nominally covered.

So what's the limit? The well at my NV place has a pH of eight and the water at my townhouse a pH of nine. Will the city's water system and/or my residential well be plugged with bacterial pseudo-cement, strong as the real stuff? (Note that the well casing has a cement wall - just ideal for them to treat the boundary between it and the dirt as a crack and follow it down.)

Lots of alkaline soil out there (like around my townhouse). Before adding so

I think that whole nanobot grey goo problem is way overhyped. Biological organisms are much more advanced than our technology and they haven't been able to turn all matter into copies of themselves yet, despite their best efforts.

Absolute worst case scenario is a grey goo outbreak being treated basically like a fire (which, when you think about it is the ultimate grey goo machine). There's a limit to how much energy is available for replication, and there's a limit on how efficient you can make your replication (at some level, the replicating nanobots will be literally tearing apart and putting back together materials). Fighting the grey goo only involves tearing about the replicators, not necessarily wasting energy putting the pieces back together into something useful.

In other words, it should be trivial to design a nanobot that tears apart the self-replicators but doesn't waste energy by making copies of itself. This nanobot would be manufactured a head of time and stored for future use, or manufactured in specialist facilities (even in a mobile truck if necessary) that provide the energy input necessary for their production. As long as your facilities have more energy available than the self-replicators do, you'll win out eventually. And the replicators will only have about as much energy available as a fire can produce.

Usually when you say that the bacteria 'likes' acidity it means that at least one of the proteins it depends on requires the acidity to function. If there are several proteins that are essential for the bacteria to live, the probability that all of the required mutations would occur becomes reasonably small. Additionally, even if the bacteria are able to mutate in such a way to live outside the concrete, they would be poorly adapted to that environment, and would most likely become food for something else.

So the assumption, as I read it, is the environment in which the bacteria is deployed is assumed to have a consistent pH level to help it identify that it is in fact, concrete. However anything that also has that pH could potentially be a hospitiable environment.

Question: How are they planning on accounting for a non-lab environment where everything from moisture, temperature, hell even lighting apparently, can influence the pH of the target location? Based on respitory infection the pH in a lung is hardly

It turns out that the press release is not really accurate with regard to the effect pH has on this engineered bacterium. The starting bacterium, Bacillus subtilis 168 naturally prefers a neutral pH, but by growing generations of this bacteria in media with gradually increased pH, it can be acclimated [igem.org] to thrive at the pH of concrete (roughly 10). This requires no engineered genetic modification. The steps to control the spread of this bacterium have little to do with pH, actually. First, the bacterium comes from a strain of Bacillus subtilis which has been produced as the result of decades of laboratory cultures, and is a mutant which depends on many key nutrients to be present in its enviroment to survive. In the wild, it would be a massively deficient competitor to wild Bacillus subtilis, which is extremely common in nature.

Also, the concrete repair activity is produced by upregulation of genes natural to Bacillus subtilis, not by anything transgenic. The upregulation of these genes presents an energy cost to the engineered bacterium while providing no benefit- if these bacteria mutate, it is more likely to be towards the wild phenotype. In addition, the team responsible has added a kill switch [igem.org] which tells the bacteria to commit suicide if sucrose is not present.

And the bacteria knows the difference between concrete and lung tissue how?

Well

Bacillus subtilis, known also as the hay bacillus or grass bacillus, is a Gram-positive, catalase-positive bacterium commonly found in soil.[3]... B. subtilis is not a human pathogen. It may contaminate food but rarely causes food poisoning.[5] B. subtilis produces the proteolytic enzyme subtilisin. B. subtilis spores can survive the extreme heat during cooking. B. subtilis is responsible for causing ropiness — a sticky, stringy consistency caused by bacterial production of long-chain polysacchar

Bone actually works like that, the osteoclasts eat the bone and their direction is controlled by electrical stimulation generated by stresses in the bone, which is followed by osteoblasts which build up the bone. This results in the bone being strongest in the direction that is most likely to be stressed.

Ah, thanks, that answers my question above -- the soil where I live is so alkaline that it's comparable to concrete. I was wondering how you'd avoid a runaway in that situation, but adding the sucrose-based nutrient-limiter routine seems to solve it well enough -- alkaline soils typically are pretty much nutrient-free.

If you've ever tried to pump glue into a crack in concrete, you'll quickly figure that out. It's somewhere between messy and inadequate as a repair method, and certainly doesn't get into the smaller cracks, let alone the microcracks. The idea here is to have the glue self-extend, filling the air pockets and microcracks that no glue with sufficient surface tension to stick could ever manage.

However I think where this will become a more useful technique is for fixing the kinds of surface cracks that ail structures exposed to repeated wet/freeze/thaw cycles -- the typical winter climate for the east slope of the Rocky Mountains. Mount Rushmore would seem to be a good candidate, since seasonal surface cracking is what's causing damage.

Concrete roads that suffer similar winter freeze/thaw damage could also benefit -- instead of trying to patch the road one crack at a time (usually an exercise in futility, culminating in yawning potholes), or having to dig up and replace the concrete (an extremely expensive job), just wash it with a slurry of this bacteria. That could even eliminate most of the seasonal damage, by filling the microcracks that are where freeze damage starts.

Imagine if your state and local highway departments could reduce their budgets by simply needing to do less repair on concrete-based roads. Even if you don't believe in reducing taxes when need is reduced, it would free up that budget to use elsewhere.

I've got no problem with using a method like this to patch concrete used for sidewalks, roads, etc. But (as an Engineer) I would have a strong reluctance to applying it to any significant structure (e.g.: Bridges, Buildings, etc.). Yes, it may fill the cracks. But what are the structural characteristics in compression, sheer, and to a lesser extent, tension? What is the bond strength with the adjacent intact concrete, as well as the reinforcing steel. How will the resultant material act over time? Co

I had the same thought... wouldn't bottom ash be essentially "distillate of everything toxic left behind by the burn process"...??

As to the other fillers... what makes concrete strong isn't just the binder, it's also (perhaps mostly) the character of the filler. Organics decompose over time. Now what.. you've got binder and decomposition products, but no filler. Explain to me how that retains its structural strength and integrity? Not only that, but with varied fillers, how do you achieve predictable struct

So basically, it had nothing at all do with the topic hand and your comparison "I'll just have bacteria in my yogurt for now" was completely meaningless since no one has suggested building new things with it since that wouldn't work anyway.

Beware the press releases.
You'll note that nowhere does the article discuss the strength of Gigacrete. They put up a few random things, but nothing like how much PSI it can withstand.
And according to their web site [gigacrete.com], "GigaCrete manufactures some of the most innovative, functional, high-performance interior finishes on the market".
Interior finish != replacement for concrete. Concrete is used as a structural material. It holds up thousands of tons of stuff. GigaCrete is an alternative to plaster. It

There are three principal parts to the filler produced by these bacteria. First, the bacterium naturally produces calcium carbonate as a byproduct of breaking down urea as a nitrogen source; this activity has been greatly increased in the engineered bacterium. The second part is a "glue" made from levan, a polysaccharide that the bacterium is able to produce from sucrose; this activity is also natural, but highly upregulated in the engineered bacterium. The final part is the bacterial cells themselves; t